Perfecting the art of the sequel: The Seiko 6105-8110

One of the defining features of my time as a casual practitioner of watchsmithery, independent of the trajectory my tastes have otherwise followed, has been a somewhat conflicted relationship with that most iconic of all Seiko divers watches, the second generation 6105. To a large extent this derives from the fact that my first watch purchase as an object of desire rather than means to an end, was a 6105-8110 from November 1976. It also formed the basis of my first tentative steps towards watch fettling (an account of my first date wheel swap can be found somewhere still on Watchuseek) an activity that now occupies a great deal of my spare time. However, while I feel great affection for this particular model, it is a watch that I have struggled to get comfortable with, something to do with a combination of its 44 mm diameter combined with the architecture on its underside not quite fitting with the boney landscape of my upper wrist and compounded by the fact that I never seemed to be able to find a strap compliant enough or whose holes were quite in the right place. As a result, I’ve tended to favour the first generation 6105 whose smaller case somehow works a bit better for me. Nevertheless, I have persisted with this watch, not least because I like it so much as an aesthetic object.

The enduring appeal of the second generation 6105-8110/9 derives from a combination of its curvy, asymmetric cushion case, with its 6-slotted locking crown nestling in the gentle curve of the crown-guard just below a cusp that sees the case edge sweeping back in-land at the 3 o’clock position.

The dial, common to both generations of the watch, is another feature that sets it apart from later incarnations of the Seiko 150 m diver’s staple. The hour markers on the 6105 feature perfect, flat-topped borders generously filled with slightly off-white luminous compound. On some 6105 dials, the markers appear to have been embossed through from the rear, whilst other, possibly later, dials have a rear free from the embossed indents, suggesting the markers are applied. However, from the front, on both types of dials, the markers emerge seamlessly from the black dial with no suggestion that they are simply glued to the surface. For this reason, there is a genuine sense of quality to the execution of the dial completely at odds with its position within the marketplace at the time.

The hands too are a vital component in the sum of parts that makes this such a wonderful watch. The hour and minute hands with their rectangular profile and beveled edges carry forward from the earlier 62MAS but the seconds hand sports a lovely playful design feature in the traffic light red dot sitting inboard of the main lumed hole at the end of the hand.

And finally, we have the coin-edge bezel,

filled with a perfectly executed slightly grained black insert, the lume pip sitting within an inverted triangle at its top, protected by a circular acrylic window.

Together these parts work to define a very Japanese watch, confident in its own design language with no sense at all that it has taken inspiration from elsewhere. In some ways this watch marks the zenith in classic Japanese watchmaking of that period, before the industry as a whole became overrun by the quartz revolution.

One of the singular hazards in finding decent examples of this watch are the numerous examples in the market place that are saddled with dire after-market dials, shiny, poorly executed reproduction handsets and terrible, ill-fitting bezel inserts. While there are strategies that one can take to minimize the impact of the latter two, if you are to gain lasting enjoyment from this watch, you must, absolutely must buy one with the best possible quality original dial. If the dial is aftermarket, don’t give it a second thought. Walk on and keep looking.

I’ve had, I think, six or seven 6105’s over the years, all but two of which second generation examples. I learned my lesson on the dial front with the first but my desire since, to find watches with the best possible dials, has been tempered somewhat by my natural inclination to secure the best possible bargain and as a result, I’ve tended to buy tatty original examples needing some cosmetic attention to get the dial in respectable shape. Consequently, of the four 6105’s I currently own, three of them have been relumed, one of which by me and the other two by professional relumers. Nevertheless, I have continued on my quest to find an example with a perfect original dial and a little over 2 years ago, I found one. It has sat since in my to-do box waiting for its number to come up, which last month, it did.

Let’s get cracking then. Here it is, in the condition received:

You should be able to appreciate straightaway that the dial is a peach, the handset pretty good, particularly the traffic light seconds hand, and that the original bezel insert is largely unmarked, a considerable feat given that the crystal looks every one of its 41 years.

I am pretty sure that the crystal is original to the watch, its higher profile serving to protect the insert from day to day knocks. While the exterior looks pretty presentable, the movement looks rather sorry for itself:

It is grubby as hell and looks to have been the subject of some rough handling but the good news is there is no sign of water ingress which means we should have the basis of a decent rebuild assuming the main plate is sound. Extracting the movement and turning it over confirms just how wonderful the dial is:

It is just about perfect. I can see no flaws or marks anywhere on its surface, the markers are completely free from corrosion or wear of any kind and the lume a perfect, slightly cream colour that heightens the vintage aesthetic. The lume on the minute hand, however, does show some discoloring and I think will need some attention if it is to be allowed to continue to keep company with the pristine dial.

For those of you still getting your eyes in as to what constitutes a decent 6105, compare and contrast the photo above with the aftermarket abomination shown here: Accept no substitutes.

Moving swiftly on, a quick look at the reverse of the dial, now removed, reveals it to have had its hour markers punched through from the rear:

whilst the calendar side of the movement looks sound if, again, a little tarnished.

With the dial and handset set safely to one side, let’s get back to the flip side, both literally and metaphorically. Pretty much as soon as I received the watch back in late 2012, I knew that the movement needed work, first and foremost because the hairspring had obviously come in for some abuse.

It is not so difficult to imagine how someone cack of hand might inflict such damage but I do wonder what might have prompted them to open up the watch in the first place. Removing the discoloured and scarred winding weight together with the autowinding mechanism exposes the train wheel bridge which looks ok.

but curiously I can see no sign of the third or fourth wheel arbors peeking through the holes in their respective bearings which makes me wonder whether the train wheel bridge had been fastened down without the train wheels properly engaged. Removing the train wheel bridge appears to confirm this as the third and fourth wheels come away with the bridge, glued in place by congealed oil.

The train wheels extracted and my fears are confirmed: at least one of the bearings on the bridge show significant signs of damage caused by the bridge being repeatedly screwed down with the third wheel arbor not having been properly engaged with its bearing hole. I fear the bridge too is a right-off.

The remainder of the movement looks dirty but otherwise ok.

As this is the later B variant of the 6105, we get a stop second facility and you can see the hacking lever in position in the photo above, its action working directly on the balance wheel rather than on the fourth wheel in the higher level 62xx series documented elsewhere.

As a final testament to its general grottiness, here’s a shot of the pallet fork jewels, both of which encrusted in congealed lubricant:

Now, what are we going to do about that knackered balance and vandalized train wheel bridge? Well, I am in the habit of acquiring bits and pieces for rainy days, and one such acquisition from ages ago was a new old stock 6106-7739 fitted with a 17 jewel hacking 6106C whose train wheel wheel bridge and balance are drop-in replacements of those in the 6105B.

Here’s the 6106C balance (left) next to the ruined balance from the 6105B:

The extracted bridge and balance from the 6106, together its train wheels join the rest of the disassembled 6105B in the ultrasonic bath and with everything cleaned, rinsed and dried, reassembly of the movement proceeded without further incident or upset (starting top right, proceeding anticlockwise):

In keeping with my intention of returning as much as possible of its original 1974 youthful vigour, I have also chosen to fit the barrel and mainspring from the 6106 donor. Next, we need to figure out what to do with the hands.

The minute hand in particular looks a bit rough but rather than choosing to relume the original hands, I opt instead to relume a pair of identical Seiko hands taken from a 6119 dress watch using the originals as a colour guide. The seconds hand is in excellent shape and so I leave that be. Here’s my first attempt to get the lume colour right:

Perhaps a touch too much yellow and so with a second, paler batch made up, I relume the replacement hands

and leave to dry over night. I reckon the colour match is pretty good

and so we are set to refit the dial spacer to the movement

followed by the dial and hands:

It’s all pretty much down hill from here, just the relative drudgery of breaking down and cleaning the case parts and fitting a fresh crystal. The case is as typically dirty as we expect of used but not pampered watches. The area around the crown tube is a bit grim but happily we can make out the presence of the locking pin, only bearing relatively minor signs of wear

The bezel levers off to expose the crystal retaining ring, helpfully equipped with a strategically positioned slot to aid removal

I tend to remove these by working a thin blade around the whole circumference before levering off. It is not uncommon for the retaining rings to be cracked or corroded and a heavy handed removal can damage them.

At this point, we can push the crystal out from beneath and then extract the bezel gasket and rehaut. The mid case itself comprises 8 separate components

The case (centre) surrounded by the crystal (top) and then working anticlockwise, the crystal retaining ring, the L-shaped bezel gasket, the rehaut, movement ring, case back and turning ring with insert. As is common with watches of this age, a ninth component, the caseback gasket is hard and brittle and in clear need of replacement:

With the case cleaned, fit first the rehaut, followed by a fresh crystal gasket

The original gasket was very dirty and hardening where it had been exposed to the elements and so unusually I felt a replacement in order

For the crystal, I elected to go for a tempered mineral facsimile of the later, lower profile double domed service replacements. You can see its shallower aspect from this comparison with the original:

and here it is fitted to the case

and now held firm with the retaining ring back in position

Well, I think we are now set to re-case the movement, having first replaced the crown with a new old stock item, whose gasket is still sufficiently supple to restore water resistance

It is my habit to fit the movement first and see that everything runs happily before refitting the autowinder, the case at that point providing a sturdy support for the procedure. The autowinder framework needs reassembling from the sum of its parts first

before reuniting with the rest of the movement

The rotor from the 6106C donor movement tops things off

and with a fresh case back gasket, we can close her up and take a look from the dial side.

Somehow I find these views before the turning ring goes back on strangely appealing. The last step then is to clean up the turning ring

fit a fresh gasket, refit, locate a suitable strap and we are there

All that remains is to try out the new strap for comfort (a very nicely executed 731 reproduction from WJean)

and finish with a few closing shots:

As sequels go, the second generation 6105 has clearly eclipsed its older sibling in the consciousness of watch collectors. It is a watch of considerable charisma, certainly iconic in its way, but for me the greater subtlety of the earlier edition just about wins the day. To set my perspective in the context of its immediate predecessors, here’s a concluding view of the refreshed second generation 6105 (right), with the first gen (centre) and the watch that started the ball rolling, the 62MAS (left).

Beautiful work, but I’m a bit confused about the abomination aftermarket dial. What is objectionable about it? I notice the hour indices aren’t as thick as the original, and there is no dash before “8009T” at the bottom. The lume color appears a different shade, but could be a result of white balance in the photo. To my untrained eyes it looks like a near enough replacement. Is it a matter of striving for full authenticity?

Thanks both. On the subject of the aftermarket dials, I almost don’t know where to begin. Let’s start with their cheap construction, the poor quality print, the rounded shiny-bordered hour markers glued to the dial, the painted, shiny green lume. Nothing about the way they are made is in keeping with the very high quality of finish and execution of the original. To fit one of these dials completely undermines the integrity of the watch for me – rendering it close to worthless as an object whose ownership one might aspire to.

Of equal, but possibly greater importance is that with the Seiko branding, the dials are unambiguously fake. Their fitment can lure the unwary into believing they are buying the genuine article. Both responses above highlight how easy it is to be taken in by the superficially tidy appearance to the aftermarket dial. I say this from a position of experience, having been fooled myself all those years ago into paying over the odds for a watch described as original but which was clearly not when I’d had time to properly appraise what I’d bought.

Thanks for your description of the difference of the dials . While I will take another good look , on the surface the only difference I really see is the lume color . YES , I would like to obtain an original dial in decent shape but they aren’t out there .
Your abhorrence to them mirrors certain members of one of the forums I belong to and to be honest I find that they [ I was going to say whine , but I won’ t ], complain too much about the AM dials on what seems to be only directed at this watch , the 6105 .
Yet I see them going Ga-ga over every modification they can come up with on any other vintage Seiko . What’s up with that ?
When I Install AM parts on this watch or any other , I do it so I can enjoy wearing a nice looking watch , BUT I will keep the originals for a future sale if that situation arises so I can pass along all its original goodness .
Understand I am only expressing MY feelings on this somewhat touchy subject , and I truly hope I don’t offend anyone .
Having said all that , once again I want to say I am a big fan of your very well presented articles….. Thanks Martin .

Louis, I admit I have a bit of a bee in my bonnet about these particular dials and this particular watch and of course everyone else is free to have their own opinions. If you read around this blog you will see plenty of examples of me using aftermarket dials in modified watches but the difference there in my mind is that the end result is not pretending to be something it is not. If I put a sterile Seamaster style dial into a Seiko diver, then no one is going to mistake it for a Seamaster – in that context I am just using the Seiko watch as a canvas to create something new. If I put a third party Seiko branded 6309 dial into a Seiko 6309 and am not completely open in a sales description on Ebay, for example, then someone may end up buying the watch thinking it is something it is not.

I guess you might ask yourself how you would feel about a Rolex Submariner 1680 fitted with a fake red 1680 dial? You are quite entitled to feel exactly the same as you do about the Seiko branded aftermarket dials, but I suspect the reaction you might get to such a modification on a Rolex forum would be a great deal more strongly expressed than a bit of whining!

Thanks for the reply Martin and I appreciate the open discussion on this or any other watch related subject .
I agree with you 100 % with honesty and disclosure in a sale of a Seiko , Rolex , or Timex . I think you hit on a good point that I hear other “purists” express on the sale of a watch . But I think that apples and oranges are getting mixed up here and I think your point is one or the other of the two . I guess my point is that it is not a crime to put an AM part on a watch if , in the eye of the wearer , it shows how nice a vintage watch can look on the wrist …..in essence , the apple .
If that same watch were to be bought and sold I think the original parts should accompany the watch for the appreciation of the original timepiece by both the buyer and the seller…the orange .
All in all Martin , this is your domain and I am pleased that we can share different perspectives here on occasion .
I look forward to the continued informative and entertaining articles you always produce .

Hi Louis, I am always very happy to discuss these things, as you say in an open and straightforward way. Of course, I don’t regard the use of such dials as a crime and what I offer is simply my opinion. I don’t pretend that my opinion in this instance is correct but it is heartfelt. In your case, if you have the original parts, then you have the flexibility to reinstate at some point if you wanted or, as you say, to continue to use the aftermarket parts as a means to have the watch looking presentable. It is your watch and you may do as you please!
Martin

Its a really interesting post about seiko 6105. Currently I own a seiko 6105-8110 and trying to restore it to a nos look condition. can you please share the info where can i find the original bezel and crown for 6105?

The bezel on my watch is the one it came with and so I cannot share any particular insight into how to secure an old stock replacement other than to keep your eyes peeled on Ebay. You may be in for quite a wait though and if you were to find one, you might be quite surprised how much they sell for on the rare occasions they appear

The crowns are quite a bit easier to find but when you do, make sure to ask about the state of the gasket. A new old stock crown with a hardened gasket is of no use to anyone. The example I used for this watch I sourced from an Ebay seller in the UK called schillachi61.

I have an original 8110 purchased in Hong Kong in1978 whilst I was a diver in the Royal Navy. I then stopped wearing it in the early to mid 80s, and it has sat in my bedside draw ever since, it was recently bought to my attention how collectable these watches are, and may be persuaded to sell it, what sort of value would you place on it? I can guarantee it’s genuine original and untouched. The glass has some heavy scratching, and the case has a small mark where I fell onto a dive boat. It has a nato strap fitted to it, because the original only lasted about 2 years.

Hi Michael, the value of these watches has inflated hugely in the past couple of years and they have been collectible for a long time. It is difficult to value a watch without a photo but ball park for original watches with clean dials start at around $1000 plus. If you read the last but one post on my blog, you may get an idea of the current market. You could also take a look at recent completed eBay listings.

one of the most informative and with excellent illustration of your craft i would love to have you restore some of my early seiko watches for my personal collection if you would consider the restoration of them i would be very great full Thank you Chris

Hi Chris, if you take a look at the ‘About’ tab, you will see that this is just a hobby for me and consequently, I do not take in work for other people. Sorry! I hope though that you are able to otherwise get some value from the blog.

Excellent feature Chris, thanks. I’ve just been lucky enough to purchase a tidy 6105-8110 from December ’75 in great condition. Are you aware of how the locking crown feature should function? I’ve only had the watch a few days and when I first set the time & date the lock mechanism seemed to work perfectly. I pushed the crown back in and then rotated it a tiny bit further until it stopped. Now I’m not sure if I imagined this or not! When I wore the watch again a day later and reset the time it didn’t seem to lock as smoothly and the crown bumped around a few times before settling. I have two questions: 1. Is the lock feature any more sophisticated than a pin that sits in one of the large crown grooves? 2. Is it supposed to prevent the crown from being pulled out? Many thanks.

Hi David, the locking function is as you describe: nothing more sophisticated than a pin that locates into one of the crown grooves. It locks only in the sense that it prevents the crown from rotating when pushed in. It does nothing to prevent you pulling the crown out.

The pins can wear away though and as they wear, so the locking function also gradually erodes away too.